Update grafana/promtail Docker tag to v2.8.4

[renovate]

This PR contains the following updates:

Package	Update	Change
grafana/promtail	patch	2.8.3 -> 2.8.4

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Release Notes

grafana/loki (grafana/promtail)

v2.8.4

Compare Source

This is release v2.8.4 of Loki.

Notable changes:

This release fixes a few vulnerabilities in Loki and our published images.

• Fix CVE-2023-1255, CVE-2023-2650, CVE-2023-2975, CVE-2023-3446, and CVE-2023-3817
• Upgrade base alpine image used in loki image to 3.18.2

Installation:

The components of Loki are currently distributed in plain binary form and as Docker container images. Choose what fits your use-case best.

Docker container:

• https://hub.docker.com/r/grafana/loki
• https://hub.docker.com/r/grafana/promtail

$ docker pull "grafana/loki:v2.8.4"
$ docker pull "grafana/promtail:v2.8.4"

Binary

We provide pre-compiled binary executables for the most common operating systems and architectures.
Choose from the assets below for the application and architecture matching your system.
Example for Loki on the linux operating system and amd64 architecture:

$ curl -O -L "https://github.com/grafana/loki/releases/download/v2.8.4/loki-linux-amd64.zip"

##### extract the binary
$ unzip "loki-linux-amd64.zip"

##### make sure it is executable
$ chmod a+x "loki-linux-amd64"

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Configuration

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🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

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